The Role of Hydroxycinnamic Acid Amide Pathway in Plant Immunity

Abstract

The compounds involved in the hydroxycinnamic acid amide (HCAA) pathway are an important class of metabolites in plants. Extensive studies have reported that a variety of plant hydroxycinnamamides exhibit pivotal roles in plant–pathogen interactions, such as p-coumaroylagmatine and ferulic acid. The aim of this review is to discuss the emerging findings on the functions of hydroxycinnamic acid amides (HCAAs) accumulation associated with plant defenses against plant pathologies, antimicrobial activity of HCAAs, and the mechanism of HCAAs involved in plant immune responses (such as reactive oxygen species (ROS), cell wall response, plant defense hormones, and stomatal immunity). However, these advances have also revealed the complexity of HCAAs participation in plant defense reactions, and many mysteries remain to be revealed. This review provides an overview of the mechanistic and conceptual insights obtained so far and highlights areas for future exploration of phytochemical defense metabolites.

In situ spatiotemporal mapping of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) inhibitor in pineapple (Ananas comosus) fruit tissue by MALDI mass spectrometry imaging

“…Since the transition of the tissue in pineapple peel and flesh is not clearly defined as these are composed predominantly of parenchymal cells with unlignified cell walls (Smith and Harris, 1995), there is the plausible translocation of N1, N10-diferuloylspermidine towards the latter region and may imply a protective effect on the ovary for defense against biotic stress such as plant-pathogen interactions. This hypothesis is supported by reports that phenolamides are a class of plant metabolites associated with plant defenses against plant pathologies and immune responses (Roumani et al, 2021;Liu et al, 2022). To our knowledge, the MALDI MSI provided the first evidence of in situ spatial localization of N1, N10diferuloylspermidine, a potential HMGCR inhibitor in pineapple while maintaining the cellular and structural features of the fruit tissues.…”

Comparative metabolomic profiling of Arabidopsis thaliana roots and leaves reveals complex response mechanisms induced by a seaweed extract

“…These three compounds belong to the sub-class hydroxycinnamic acids (HCAs), which is broadly defined as a group of compounds derived from cinnamic acid ( El-Seedi et al., 2012 ). HCAs play an essential role in plant immunity by enhancing antimicrobial effects, strengthening cell walls, and mediating stomatal activity ( Liu et al., 2022 ), which contribute to protecting plants against biotic and abiotic stress ( Macoy et al., 2015 ). Reduced accumulations of phenylpropanoid compounds in our study compared with other studies may be a result of the dependence of their activity on the bioactive components, which are often species specific and even showed differences between extracts derived from the same seaweed species ( De Saeger et al., 2019 ; Ali et al., 2021 ; Shukla et al., 2021 ).…”

Bacillus vallismortis TU-Orga21 blocks rice blast through both direct effect and stimulation of plant defense

“…The biomolecule–related intensities from average spectra revealed significantly higher agglomeration of Amide I (1,600–1,800 cm -1 ) and Amide II (1,470–1,570 cm -1 ) proteins. A plant protein peptide bond is an amide group as well as a type of endogenous factor in disease resistance to encourage plant–microbe interaction ( Liu et al., 2022 ). Plant peptides induce immune responses that are established at the receptor level of plant peptides in response to pathogen invasion, including the induction of defense–related phytoalexin, lignification, and PR proteins ( Hu et al., 2018 ; Kumar et al., 2018 ).…”